I don't think collapsing multiple red tapes into one means you won't be able to stack up the old red tapes, rather it means there will be one new red tape nano that debuffs the same/slightly more/slightly less than the current stack does.
To avoid a ridiculous amount of debuff, all FC would need to do is put the new nano into the same nanolines as the other red tapes, so if the 3x red tapes debuffs for more, you still have that option, or if you need to cut your casting a bit, like for PvP, you can cast the new single.
In fact, this gave me an idea for a suggestion to the new "collapsed" red tape.
When you execute the new red tape, on a successful land, it should drop 3 nanos on the target, NRT 1 2 and 3. Debuffs 350, 200 and 200 each for a total of -750. On a successful land, it puts a local lockout (a la new stuff NTs are getting, a la ICH, a la DM) that stops you from keeping the new collapsed one perma running on the target.
BUT, you can overwrite NRT1 with Nanite Advanced RT, NRT2 with Normalised, NRT3 with IRT, etc etc.
Hope this makes sense, I've just woken up. Keeping a target debuffed (and debuffed for more) will still require the old tapes, but in a faster paced environment where -750 is better than -400 then -250 then -250 due to the time taken, we have another option.
What do you guys think?